Fiber optic connector preventing relative rotation between components

ABSTRACT

An optical fiber connector sub-assembly for an optical fiber connector includes a ferrule configured to hold an optical fiber therein, a ferrule holder configured to hold the ferrule, a retaining tube configured to hold the ferrule holder and receive a fiber optic cable, and a connecting tube configured to be rotatingly coupled with the ferrule holder and slidingly received by the retaining tube. The ferrule holder, the retaining tube, and the connecting tube are configured to receive an optical fiber, and the retaining tube and the connecting tube are configured to cooperate with one another to prevent relative rotation between the ferrule holder and the retaining tube.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No.62/860,283, filed Jun. 12, 2019. The disclosure of the prior applicationis hereby incorporated by reference herein in its entirety.

BACKGROUND

The present disclosure relates to an optical fiber connector, forexample, an LC (Lucent Connector) connector. More particularly, thedisclosure relates to a fiber optic connector that prevents a fiber thatis connected to the connector from rotating relative to the connectorwhen being pushed through a duct or conduit.

The mechanical tolerances involved in terminating single mode opticalfiber are much tighter than those for multimode optical fiber.Therefore, while it is quite common for multimode optical fiber beterminated at the point of use, for example, at a user's premises or atan outside junction box, in most product applications, single modeoptical fiber is not terminated in the field. When single mode fibermust be terminated in the field, then it can take a skilled technicianbetween about 15 to 20 minutes to splice fibers together either by usinga V-groove clamp or expensive fusion welding equipment.

Single mode fiber is therefore often provided in a range of differentlengths, pre-terminated at both ends with a connector that is configuredto be connected with an outer housing after the pre-terminated end isdeployed to its desired location. The pre-terminated end and housing isthen ready to plug into a matching receptacle.

One example of such a connector is an LC connector. The LC connector andadapters were originally developed by Lucent Technologies. The LCconnector is a miniaturized version of the fiber optic SC (SubscriberConnector) connector, thus being also known as a small form factorconnector. The LC connector looks somewhat similar to the SC connector,but is about half the size with a 1.25 mm ferrule instead of a 2.5 mmferrule. LC connectors are typically composed of a plastic housing withan RJ45 push-pull style clip.

Conventional optical fiber LC connectors comprise a rigid pushablestructure to allow for limited movement of the connector parts whilebeing pushed down stretches of duct. However, conventional optical fiberLC connectors permit rotation between the fiber and the connector whenthe connector is being pushed through the duct. Such rotation couldcause damage to the fiber, which may result in signal degradation orsignal loss.

Therefore, it may be desirable to provide an optical fiber connectorthat prevents rotation of the fiber relative to the connector whilebeing pushed through a duct or conduct.

SUMMARY

In accordance with various embodiments of the disclosure, an opticalfiber connector sub-assembly for an optical fiber connector includes aferrule configured to hold an optical fiber therein along an axis of theconnector, a ferrule holder configured to hold the ferrule at a frontportion of the connector, a retaining tube having a front end portionconfigured to hold the ferrule holder and a rear end portion configuredto receive a fiber optic cable, and a connecting tube configured to bereceived in the ferrule holder in a press fit relationship such that theconnecting tube is rotatingly coupled with the ferrule holder, and theconnecting tube being configured to be slidingly received by theretaining tube. The ferrule holder, the retaining tube, and theconnecting tube are configured to receive an optical fiber, and theferrule is configured to terminate the optical fiber. The connectingtube includes a head portion having a flattened region, and wherein theretaining tube includes an inner wall having a flattened inner regionconfigured to be aligned with the flattened region of the connectingtube to prevent relative rotation between the ferrule holder and theretaining tube.

According to various aspects, a fiber optic connector includes theaforementioned optical fiber connector sub-assembly and an outer housingconfigured to be coupled with the optical fiber connector sub-assembly.The outer housing is configured to provide LC-style push/pullengagement/disengagement with a mating optical fiber socket.

In some aspects, the retaining tube includes a forward end portion and arearward end portion, the forward end portion and the rearward endportion being separated at an interior of the retaining tube by an innerannular shoulder.

In various aspects, the forward end portion of the retaining tubeincludes a bore configured to slidingly receive at least a portion ofthe cylindrical stem portion of the ferrule holder, the rearward endportion of the retaining tube includes a bore configured to slidinglyreceive the connecting tube, and the connecting tube extends through abore defined by the inner annular shoulder.

According to some aspects, the head portion of the elongated cylindricalportion of the connecting tube includes at least one additionalflattened region, and the inner wall of the rearward end portion of theretaining tube includes at least one additional flattened inner regionconfigured to be aligned with the at least one additional flattenedregion of the connecting tube.

According to various embodiments of the disclosure, an optical fiberconnector sub-assembly for an optical fiber connector includes a ferruleconfigured to hold an optical fiber therein, a ferrule holder configuredto hold the ferrule, a retaining tube having a front end portionconfigured to hold the ferrule holder and a rear end portion configuredto receive a fiber optic cable, and a connecting tube configured to berotatingly coupled with the ferrule holder and slidingly received by theretaining tube. The ferrule holder, the retaining tube, and theconnecting tube are configured to receive an optical fiber, and theconnecting tube includes a head portion having a flattened region. Theretaining tube includes an inner wall having a flattened inner regionconfigured to be aligned with the flattened region of the connectingtube to prevent relative rotation between the ferrule holder and theretaining tube.

According to various aspects, a fiber optic connector includes theaforementioned optical fiber connector sub-assembly and an outer housingconfigured to be coupled with the optical fiber connector sub-assembly.The outer housing is configured to provide LC-style push/pullengagement/disengagement with a mating optical fiber socket.

In some aspects, the retaining tube includes a forward end portion and arearward end portion, the forward end portion and the rearward endportion being separated at an interior of the retaining tube by an innerannular shoulder.

In various aspects, the forward end portion of the retaining tubeincludes a bore configured to slidingly receive at least a portion ofthe cylindrical stem portion of the ferrule holder, the rearward endportion of the retaining tube includes a bore configured to slidinglyreceive the connecting tube, and the connecting tube extends through abore defined by the inner annular shoulder.

According to some aspects, the head portion of the elongated cylindricalportion of the connecting tube includes at least one additionalflattened region, and the inner wall of the rearward end portion of theretaining tube includes at least one additional flattened inner regionconfigured to be aligned with the at least one additional flattenedregion of the connecting tube

In accordance with various embodiments of the disclosure, an opticalfiber connector sub-assembly for an optical fiber connector includes aferrule configured to hold an optical fiber therein, a ferrule holderconfigured to hold the ferrule, a retaining tube configured to hold theferrule holder and receive a fiber optic cable, and a connecting tubeconfigured to be rotatingly coupled with the ferrule holder andslidingly received by the retaining tube. The ferrule holder, theretaining tube, and the connecting tube are configured to receive anoptical fiber, and the retaining tube and the connecting tube areconfigured to cooperate with one another to prevent relative rotationbetween the ferrule holder and the retaining tube.

According to various aspects, a fiber optic connector includes theaforementioned optical fiber connector sub-assembly and an outer housingconfigured to be coupled with the optical fiber connector sub-assembly.The outer housing is configured to provide LC-style push/pullengagement/disengagement with a mating optical fiber socket

In some aspects, the retaining tube includes a forward end portion and arearward end portion, the forward end portion and the rearward endportion being separated at an interior of the retaining tube by an innerannular shoulder.

In various aspects, the forward end portion of the retaining tubeincludes a bore configured to slidingly receive at least a portion ofthe cylindrical stem portion of the ferrule holder, the rearward endportion of the retaining tube includes a bore configured to slidinglyreceive the connecting tube, and the connecting tube extends through abore defined by the inner annular shoulder.

According to some aspects, the connecting tube includes an elongatedcylindrical portion having a head portion at its rear end, the headportion including a flattened region, and the rearward end portion ofthe retaining tube includes an inner wall having a flattened innerregion configured to be aligned with the flattened region of theconnecting tube.

According to various aspects, the head portion of the elongatedcylindrical portion of the connecting tube includes at least oneadditional flattened region, and the inner wall of the rearward endportion of the retaining tube includes at least one additional flattenedinner region configured to be aligned with the at least one additionalflattened region of the connecting tube.

In some aspects, a forward end portion of the connecting tube isconfigured to be received in the ferrule holder in a press fitrelationship such that the connecting tube is rotatable with the ferruleholder.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be further described, by way ofexample only, and with reference to the accompanying drawings, in which:

FIG. 1 is an exploded perspective view of an exemplary fiber opticconnector in accordance with various aspects of the disclosure;

FIG. 2 is a perspective view of the connector subassembly of the fiberoptic connector of FIG. 1;

FIG. 3 is a cross-sectional perspective view of the connectorsubassembly of FIG. 2;

FIG. 4 is a cross-sectional view of a portion of the connectorsubassembly of FIG. 2;

FIG. 5 is a perspective view of the fiber optic connector of FIG. 1;

FIG. 6 is a perspective view of a portion of the fiber optic connectorof FIG. 1;

FIG. 7 is a perspective view of another exemplary fiber optic connectorin accordance with various aspects of the disclosure;

FIG. 8 is a cross-sectional perspective view of the connectorsubassembly of FIG. 7;

FIG. 9 is a cross-sectional perspective view of the connectorsubassembly of FIG. 7;

FIG. 10 is an exploded, cross-sectional perspective view of theconnector subassembly of FIG. 7;

FIG. 11 is an exploded, cross-sectional perspective view of a portion ofthe connector subassembly of FIG. 7;

FIG. 12 is a perspective view of another connector sub-assembly for thefiber optic connector of FIG. 7;

FIG. 13 is a cross-sectional perspective view of the connectorsubassembly of FIG. 12; and

FIG. 14 is a cross-sectional perspective view of a portion of theconnector subassembly of FIG. 12.

DETAILED DESCRIPTION OF EMBODIMENTS

FIGS. 1-6 illustrate an exemplary fiber optic connector 100, forexample, an LC connector, in accordance with various aspects of thedisclosure. The fiber optic connector 100 includes a connectorsub-assembly 102 and an outer housing 104. In some aspects, the outerhousing 104 may be an LC housing configured to be received by aconventional matching LC receptacle. That is, the outer housing 104 maybe configured to provide LC-style push/pull engagement/disengagementwith a mating optical fiber socket (not shown). The fiber opticconnector 100 is configured to be coupled with a fiber optic cable 106.For example, an end of the cable 106 is configured to be terminated withthe connector sub-assembly 102.

The connector sub-assembly 102 includes an elongate cylindrical opticalfiber ferrule 112 having at one end a termination end 114. In thisexample, the ferrule 112 is of a ceramic material, although othermaterials may be used, as is known in the art. The ferrule 112 has anaxis 116 that extends centrally through the fiber optic connector 100,and along its axis 116 has a hollow core 118 that holds and aligns anoptical fiber 108 of the cable 106, which will most often be a singlemode glass fiber. The person skilled in the art will recognize this as aconventional arrangement, in which the fiber 108 is terminated at theferrule termination end 114, which is polished to minimize insertionloss when the connector is joined to a matching optical fiber socket(not shown).

The connector sub-assembly 102 also includes a ferrule holder 120, agenerally cylindrical retaining tube 130, and a connecting tube 140. Theferrule holder 120 has a base portion 122 at its forward end in whichthe ferrule 112 is seated, a collar 123, and a cylindrical stem portion124 which extends from the collar 123 in an axial direction away fromthe ferrule 112. The collar 123 includes an external annular shoulder126 and an internal annular shoulder 128. The base portion 122 isconfigured to receive the ferrule 112 in a press-fit relationship with arear face of the ferrule 122 abutting a forward face 127 a of theinternal annular shoulder 128, as would be understood by persons skilledin the art.

The retaining tube 130 includes a forward end portion 132 and a rearwardend portion 134. The forward end portion 132 and the rearward endportion 134 are separated at an interior of the retaining tube 130 by aninner annular shoulder 136. The forward end portion 132 includes anexternal shoulder portion 133 defining a rearward facing surface. Theforward end portion 132 includes a bore 131 configured to slidinglyreceive at least a portion of the cylindrical stem portion 124 of theferrule holder 120. The rearward end portion 134 includes a bore 135configured to slidingly receive the connecting tube 140, which extendsthrough a closely fitting bore 137 defined by the inner annular shoulder136.

The connecting tube 140 includes an elongated cylindrical portion 141having a head portion 142 at its rear end. The head portion 142 has alarger cross-section in a plane perpendicular to the ferrule axis thandoes the elongated cylindrical portion 141. The head portion 142 may begenerally cylindrical, but includes a flattened region 143 that forms,for example, a chord, such that the head portion 142 is formed in aD-shape as viewed in the axial direction.

A forward end portion of the elongated cylindrical portion 141 isconfigured to be received in the cylindrical stem portion 124, forexample, in a press fit relationship, more particularly, a light pressfit connection. The press fit relationship should be sufficient suchthat the connecting tube 140 is rotatable with the cylindrical stemportion 124 about ferrule axis 116 and not rotatable relative to thecylindrical stem portion 124 when the connector subassembly 102 is beingpushed through a duct or conduct. The forward end face 144 at theforward end portion of the elongated cylindrical portion 141 abuts arearward face 127 b of the internal annular shoulder 128 of the collar123. A forward face 146 of the head portion 142 abuts a rearward face136 a of the inner annular shoulder 136 of the retaining tube 130.

The rearward end portion 134 of the retaining tube 130 includes a smallinner diameter portion 150 adjacent the inner annular shoulder 136 and alarge inner diameter portion 152 extending axially from the small innerdiameter portion 150 in a direction away from the inner annular shoulder136. The large inner diameter portion 152 has a larger inside diameterthan the small inner diameter portion 150. The retaining tube 130 mayinclude a tapered or stepped transition between the small inner diameterportion 150 and the large inner diameter portion 152.

The large inner diameter portion 152 is sized and configured to receivethe cable 106, including a sheath 107 that protects the fiber 108. Afterreceiving the cable 106, including the sheath 107, the large diameterportion 152 is crimped onto the sheath 107 of the cable 106, as shown inFIGS. 1 and 2. The small inner diameter portion 150 has a smallerdiameter than the outside diameter of the sheath 107 and is thus sizedand configured to prevent the sheath 107 from entering the smalldiameter portion 150. However, the small inner diameter portion 150 issized and configured to receive the fiber 108 and buffering layers 109that encircle the fiber 108 and are encircled by the sheath 107. Thus,the transition between the small inner diameter portion 150 and thelarge inner diameter portion 152 provides a stop for limiting the axialinsertion of the cable 106 into the retaining tube 130.

The small diameter portion 150 of the retaining tube 130 includes adeformed region 151 that protrudes radially inward from an inner wall135 a of the bore 135 of the small diameter portion 150. The deformedregion 151 may be formed by controlled peening, crimping, or the like.The deformed region 151 forms an indent having a flattened inner region151 a configured to be aligned with the flattened region 143 of the headportion 142 of the connecting tube 140. When the head portion 142 of theconnecting tube 140 is received in the generally cylindrical bore smalldiameter portion 150 of the retaining tube 130, the deformed region 151cooperates with the flattened region 143 of the head portion 142 toprevent relative rotation between the connecting tube 140 and theretaining tube 130.

The connector sub-assembly 102 further includes a coil spring 160disposed between the connecting tube 140 and the retaining tube 130 in aradial direction and retained in an axial direction between a rear endface 125 of the cylindrical stem portion 124 and a forward face 138 ofthe inner annular shoulder 136. The coil spring 160 biases the ferruleholder 120 forwardly relative to the retaining tube 130, with theforward bias being limited by the abutment between the forward face 146of the head portion 142 and the rearward face 136 a of the inner annularshoulder 136 of the retaining tube 130. The coil spring 160 iscompressible in the axial direction by axial sliding movement of thestem portion 124 relative to the retaining tube 130. The axial range oftravel of the ferrule holder 120 and connecting tube 140 is determinedby the axial length of the small inner diameter portion 150 of theretaining tube 130, as shown in FIG. 4.

The connector 100 may further include a removable protective cap 162having a bore configured to receive the ferrule 112. The connector 100may also include a tubular member 164 having a through bore configuredto receive the fiber 108 and the buffering layers 109 and to be insertedbetween the buffering layers 109 and the sheath 107 at the end of thesheath 107. The tubular member 164 may protect the fiber 108 duringcrimping of the large diameter portion 152 of the retaining tube 130.The tubular member 164 includes an outer shoulder 166 at its forward endto limit insertion of the tubular member 164 into the sheath 107 of thecable 106. The small inner diameter portion 150 is sized and configuredto receive the outer shoulder 166. The connector 100 may also include aboot 168 around the cable 106 that is configured to abut the rearwardend of the connecting tube 130 and the rearward end of the outer housing104. The boot 168 is configured to provide strain relief for the cable106 and a weather resistant seal at the rearward end of the connector100.

The outer housing 104 is configured in a substantially square shape witha release lever 108 projecting outward from a top wall 174 of the outerhousing 104, for example, as is typical with conventional LC connectors.The outer housing 104 includes a through bore 170 configured to receivethe connector sub-assembly 102 such that the ferrule 112 can be exposedat a front end 172 of the outer housing 104. The inner surfaces of thetop wall 174 and a bottom wall 176 of the outer housing 104 includealignment ribs 178. The alignment ribs 178 are configured to be receivedby axial alignment channels 129, 139 in the outer walls of the ferruleholder 120 and the retaining tube 130, respectively. The alignmentchannels 129, 139 are disposed at diametrically opposed top and bottomportions of the ferrule holder 120 and the retaining tube 130,respectively. In some aspects, the outer wall of the ferrule holder 120may include only a single alignment rib, and the outer housing mayinclude only a single alignment channel.

The alignment ribs 178 are tapered from a first width (i.e., in adirection perpendicular to the ferrule axis) at a forward end 180 to asecond width at a rearward end 182. The first width of the ribs 178substantially matches a width of the alignment channels 129, 139. Thetapered profile allows freedom of movement and the rearward end 182 ofthe ribs 178 serves as a hard stop relative to a rearward end of thealignment channels 139 of the retaining tube 130.

The outer housing 104 further includes side walls 184 having resilientfingers 185 extending inward into the through bore 170. Each of theresilient fingers 185 may be cantilevered at its rear end 186, and thefree forward end 188 of each finger 185 is configured to engage therearward facing surface of the external shoulder portion 133 of theforward end portion 132 of the retaining tube 130 when the retainingtube 130 is inserted into the outer housing 104 to couple the housing104 with the sub-assembly 102.

Referring now to FIGS. 7-11, another exemplary fiber optic connector700, for example, an LC connector, in accordance with various aspects ofthe disclosure is illustrated. The exemplary fiber optic connector 700is similar to the fiber optic connector described above, except that thesmall diameter portion 750 of the retaining tube 730 includes across-sectional profile 751 along its length that matches the D-shapedprofile of the head portion 742 of the connecting tube 740. When thehead portion 142 of the connecting tube 740 is received in the generallycylindrical bore small diameter portion 750 of the retaining tube 730,the cross-sectional profile 751 cooperates with the D-shaped profile ofthe head portion 742 to prevent relative rotation between the connectingtube 740 and the retaining tube 730.

As shown in FIGS. 8-10, the outer walls of the ferrule holder 720 andthe retaining tube 730 may be generally cylindrical with flattenedregions 729, 739 that are aligned with one another. The outer housing704 may include a bore having a top wall 774 with a flattened innersurface 778 configured to be aligned with the flattened regions 729, 739of the ferrule holder 720 and the retaining tube 730, respectively, toprevent relative rotation between the outer housing 704 and theconnector sub-assembly 702.

Referring now to FIGS. 12-14, another exemplary fiber optic connectorsubassembly 1204 in accordance with various aspects of the disclosure isillustrated. The exemplary fiber optic connector sub-assembly is for usewith the fiber optic connector 700, and is similar to the fiber opticconnector sub-assemblies 102, 702 described above, except that headportion 1242 of the connecting tube 1240 has a hex profile, and thesmall diameter portion 1250 of the retaining tube 1230 includes amatching hex profile 1251 along its length. When the head portion 1242of the connecting tube 1240 is received in the generally cylindricalbore small diameter portion 1250 of the retaining tube 1230, thecross-sectional hex profile 1251 cooperates with the hex profile of thehead portion 1242 to prevent relative rotation between the connectingtube 1240 and the retaining tube 1230.

It should be appreciated that although the outer housing 104 isillustrated as transparent to facilitate an understanding of theconnector, the outer housing is not typically transparent.

It should be noted that although the specific example described aboverelates to LC-type connectors, the optical fiber connector sub-assemblycan be adapted for use with other types of optical fiber connectorsystems, for example SC-type connectors and ST-type connectors.

Additional embodiments include any one of the embodiments describedabove, where one or more of its components, functionalities orstructures is interchanged with, replaced by or augmented by one or moreof the components, functionalities, or structures of a differentembodiment described above.

It should be understood that various changes and modifications to theembodiments described herein will be apparent to those skilled in theart. Such changes and modifications can be made without departing fromthe spirit and scope of the present disclosure and without diminishingits intended advantages. It is therefore intended that such changes andmodifications be covered by the appended claims.

Although several embodiments of the disclosure have been disclosed inthe foregoing specification, it is understood by those skilled in theart that many modifications and other embodiments of the disclosure willcome to mind to which the disclosure pertains, having the benefit of theteaching presented in the foregoing description and associated drawings.It is thus understood that the disclosure is not limited to the specificembodiments disclosed herein above, and that many modifications andother embodiments are intended to be included within the scope of theappended claims. Moreover, although specific terms are employed herein,as well as in the claims which follow, they are used only in a genericand descriptive sense, and not for the purposes of limiting the presentdisclosure, nor the claims which follow.

What is claimed is:
 1. An optical fiber connector sub-assembly for anoptical fiber connector, comprising: a ferrule configured to hold anoptical fiber therein along an axis of the connector; a ferrule holderconfigured to hold the ferrule at a front portion of the connector; aretaining tube having a front end portion configured to hold the ferruleholder and a rear end portion configured to receive a fiber optic cable;a connecting tube configured to be received in the ferrule holder in apress fit relationship such that the connecting tube is rotatinglycoupled with the ferrule holder, and the connecting tube beingconfigured to be slidingly received by the retaining tube; wherein theferrule holder, the retaining tube, and the connecting tube areconfigured to receive an optical fiber; wherein the ferrule isconfigured to terminate the optical fiber; wherein the connecting tubeincludes a head portion having a flattened region and wherein theretaining tube includes an inner wall having a flattened inner regionconfigured to be aligned with the flattened region of the connectingtube to prevent relative rotation between the ferrule holder and theretaining tube.
 2. A connector comprising: the optical fiber connectorsub-assembly of claim 1; and an outer housing configured to be coupledwith the optical fiber connector subassembly.
 3. The connector of claim2, wherein the outer housing is configured to provide Lucent Connection(LC) push/pull engagement/disengagement with a mating optical fibersocket.
 4. The optical fiber connector sub-assembly of claim 1, whereinthe retaining tube includes a forward end portion and a rearward endportion, the forward end portion and the rearward end portion beingseparated at an interior of the retaining tube by an inner annularshoulder.
 5. The optical fiber connector sub-assembly of claim 4,wherein the forward end portion of the retaining tube includes a boreconfigured to slidingly receive at least a portion of the ferruleholder; wherein the rearward end portion of the retaining tube includesa bore configured to slidingly receive the connecting tube; and whereinthe connecting tube extends through a bore defined by the inner annularshoulder.
 6. The optical fiber connector sub-assembly of claim 1,wherein the head portion of the connecting tube includes at least oneadditional flattened region; and wherein the inner wall of the rearwardend portion of the retaining tube includes at least one additionalflattened inner region configured to be aligned with the at least oneadditional flattened region of the connecting tube.
 7. The optical fiberconnector sub-assembly of claim 1, wherein the head portion includes aradially outward facing surface having the flattened region which formsa chord of the radially outward facing surface; and wherein the innerwall includes radially inward facing surface having the flattened innerregion configured to face the flattened region of the radially outwardfacing surface of the head portion.
 8. An optical fiber connectorsub-assembly for an optical fiber connector, comprising: a ferruleconfigured to hold an optical fiber therein; a ferrule holder configuredto hold the ferrule; a retaining tube having a front end portionconfigured to hold the ferrule holder and a rear end portion configuredto receive a fiber optic cable; a connecting tube configured to bereceived in and rotatingly coupled with the ferrule holder and slidinglyreceived by the retaining tube; wherein the ferrule holder, theretaining tube, and the connecting tube are configured to receive anoptical fiber; wherein the connecting tube includes a head portionhaving a flattened region; and wherein the retaining tube includes aninner wall having a flattened inner region configured to be aligned withthe flattened region of the connecting tube to prevent relative rotationbetween the ferrule holder and the retaining tube.
 9. A connectorcomprising: the optical fiber connector sub-assembly of claim 8; and anouter housing configured to be coupled with the optical fiber connectorsubassembly.
 10. The connector of claim 9, wherein the outer housing isconfigured to provide Lucent Connection (LC) push/pullengagement/disengagement with a mating optical fiber socket.
 11. Theoptical fiber connector sub-assembly of claim 8, wherein the retainingtube includes a forward end portion and a rearward end portion, theforward end portion and the rearward end portion being separated at aninterior of the retaining tube by an inner annular shoulder.
 12. Theoptical fiber connector sub-assembly of claim 11, wherein the forwardend portion of the retaining tube includes a bore configured toslidingly receive at least a portion of the ferrule holder; wherein therearward end portion of the retaining tube includes a bore configured toslidingly receive the connecting tube; and wherein the connecting tubeextends through a bore defined by the inner annular shoulder.
 13. Theoptical fiber connector sub-assembly of claim 8, wherein the headportion of the connecting tube includes at least one additionalflattened region; and wherein the inner wall of the rearward end portionof the retaining tube includes at least one additional flattened innerregion configured to be aligned with the at least one additionalflattened region of the connecting tube.
 14. The optical fiber connectorsub-assembly of claim 8, wherein the head portion includes a radiallyoutward facing surface having the flattened region which forms a chordof the radially outward facing surface; and wherein the inner wallincludes radially inward facing surface having the flattened innerregion configured to face the flattened region of the radially outwardfacing surface of the head portion.
 15. An optical fiber connectorsub-assembly for an optical fiber connector, comprising: a ferruleconfigured to hold an optical fiber therein; a ferrule holder configuredto hold the ferrule; a retaining tube configured to hold the ferruleholder and receive a fiber optic cable; a connecting tube configured tobe received in and rotatingly coupled with the ferrule holder andslidingly received by the retaining tube; wherein the ferrule holder,the retaining tube, and the connecting tube are configured to receive anoptical fiber; and wherein the retaining tube and the connecting tubeare configured to cooperate with one another to prevent relativerotation between the ferrule holder and the retaining tube.
 16. Aconnector comprising: the optical fiber connector sub-assembly of claim15; and an outer housing configured to be coupled with the optical fiberconnector subassembly.
 17. The connector of claim 16, wherein the outerhousing is configured to provide Lucent Connection (LC) push/pullengagement/disengagement with a mating optical fiber socket.
 18. Theoptical fiber connector sub-assembly of claim 15, wherein the retainingtube includes a forward end portion and a rearward end portion, theforward end portion and the rearward end portion being separated at aninterior of the retaining tube by an inner annular shoulder.
 19. Theoptical fiber connector sub-assembly of claim 18, wherein the forwardend portion of the retaining tube includes a bore configured toslidingly receive at least a portion of the ferrule holder; wherein therearward end portion of the retaining tube includes a bore configured toslidingly receive the connecting tube; and wherein the connecting tubeextends through a bore defined by the inner annular shoulder.
 20. Theoptical fiber connector sub-assembly of claim 18, wherein the connectingtube includes an elongated cylindrical portion having a head portion atits rear end, the head portion including a flattened region; and whereinthe rearward end portion of the retaining tube includes an inner wallhaving a flattened inner region configured to be aligned with theflattened region of the connecting tube.
 21. The optical fiber connectorsub-assembly of claim 20, wherein the head portion of the connectingtube includes at least one additional flattened region; and wherein theinner wall of the rearward end portion of the retaining tube includes atleast one additional flattened inner region configured to be alignedwith the at least one additional flattened region of the connectingtube.
 22. The optical fiber connector sub-assembly of claim 20, whereinthe head portion includes a radially outward facing surface having theflattened region which forms a chord of the radially outward facingsurface; and wherein the inner wall includes radially inward facingsurface having the flattened inner region configured to face theflattened region of the radially outward facing surface of the headportion.
 23. The optical fiber connector sub-assembly of claim 18,wherein a forward end portion of the connecting tube is configured to bereceived in the ferrule holder in a press fit relationship such that theconnecting tube is rotatable with the ferrule holder.